The amount of resin required to fill the sprue of a plastic mould

The amount of resin required to fill the sprue, runner and cavities of a plastic mould comprises a "shot". Trapped air in the mould can escape through air vents that are ground into the parting line of the plastic injection mould, or around ejector pins and slides that are slightly smaller than the holes retaining them. If the trapped air is not allowed to escape, it is compressed by the pressure of the incoming material and squeezed into the corners of the cavity, where it prevents filling and can also cause other defects. The air can even become so compressed that it ignites and burns the surrounding plastic material.

Pallet moudle

MASTER plastic mold

MASTER plastic mold

With the increasing precision china plastic injection molding , in addition to the correct selection and selected MASTER plastic pallet mould , how to choose the molding process conditions, a reasonable comprehensive analysis of the relationship between the shrinkage products and process among the parameters, and for various reasons and processing factors that affect it and so produce shrinkage is a very important issue. Starting from the gate until the release of the entire period of solidification cooling phase. At this stage no other new melt into the mold cavity, piece weight and density PE products not change. The cooling process, the MASTER thin wall moulding shrinkage of the article temperature and cooling rate, cooling time concerned, cooling speed, article no time relaxation, shrinkage ratio may be smaller; if the mold temperature is high, the cooling rate is slow, sufficient relaxation time of the molecule, contraction rates may increase.